Key Stats That Shape This Week's NRL Preliminary Finals

There won't be many out there arguing the four best aren't playing off for a place in the Grand Final this week.

Each have displayed the quality and consistency of potential premiers, but they need to win two more games to get there.

Here, we take a look at the key areas all four sides will need to give special attention to if they're to feature in next week's Grand Final.

Melbourne Storm

The Storm appear to have finally found their first-choice number seven. After struggling through the first five games of the season, Brodie Croft was dropped to reserve grade. He returned in Round 17 for two weeks before spending more time away from the team until Round 23. Since then - minus the game he missed through injury - Croft has been out there every week.

Since his early-season stint in reserve grade, Croft has returned to put a lot more emphasis on his running game. He's running the ball more, generating more metres, and registering more line engaged runs than earlier in the year. His average of 4.2 line engaged runs per game in his last five has Croft up with the top running halves this season.

Stop.

It!#NRLStormSouths#NRLFinals#NRL pic.twitter.com/FAemPuGQtU

— NRL (@NRL) September 7, 2018

When Croft gives the defence something to worry about, it opens up opportunities for Billy Slater, Cameron Munster and Cameron Smith. Croft might be the smallest piece of the spine, but he could be one of the biggest influences on Friday.

That won't happen if the Storm can't hold onto the ball, though.

Leading the way in handling errors with 4.4 per game, Cronulla will attempt to apply pressure and expose that unwanted element of Melbourne's game.

Contributing to their below average completion rate (76.2%) while causing them to average more incomplete sets than anybody (9.1 per game), the Storm need to clean up the handling errors, have Croft run the ball, and let the rest take care of itself.

Cronulla Sharks

Shane Flanagan left no doubt that the Sharks aren't going to take any of the Storm's wrestling tactics lying down.

"The point that I think everyone misses is we're just not going to put up with any of their crap. If they wrestle, push or shove ... we'll stand up to them."

Lucky for them, Cronulla are just as good and can give it as well as they can take it.

The 3.65-second play-the-ball average the Sharks allow their opposition to play with is the second slowest in the competition. Melbourne are widely regarded as the masters of the wrestle, but Cronulla aren't too bad themselves.

They'll want to adopt every trick they know to slow down the Storm. With a taste of their own medicine, the Sharks will go a long way towards frustrating the Storm into making errors. The Sharks have won both games between the two in 2018; their niggle and willingness to do the dirty work played a large part in forcing 12.5 errors in each.

With the extra possession, the Sharks can work on getting up the field.

Averaging 1,550 metres per game, the Sharks are fourth in the competition for running metres. Having won 10 of the 13 games they've cleared that number, the Storm will have the middle of the field circled as the area they'll attempt to slow the Sharks down the most.

Sydney Roosters

It's no coincidence that the four best defensive teams in the NRL this season are the only ones left just one game short of the Grand Final.

Defence wins premierships and the Roosters are the best of the bunch conceding just 14.9 points per game.

They do it by averaging the fourth-most tackles per game (330.8) while missing the second fewest (27). Third in offside penalties per game, the Roosters aren't afraid to push the envelope and risk a repeat set on their own line if it means they get a slight rest. However, when they do make the tackle, they commit fewer penalties in the play-the-ball than any other team.

Claiming defence as the key to victory is hardly a revelation, but it's more important this week than most.

With Latrell Mitchell suspended, the Chooks lose one of their best-attacking weapons. When they're getting up the field and dominating through the middle, Mitchell is receiving and running the football on the edge. When he runs, the Roosters tend to win.

Random Stat/s: Latrell Mitchell averages 7.78 runs per game.

When he runs less than that, the Roosters are 5W-6L.

When he runs more, they are 10W-2L.

— Jason Oliver (@JasonNRL) September 18, 2018

Given the Roosters attack will lack some of its punch on Saturday, their defence needs to make up the difference.

South Sydney Rabbitohs

Scoring 24 points per game in 2018, the Rabbitohs lead the NRL in attack. When they're switched on and at their best, there isn't a better sight in rugby league right now.

While they're relatively strong in every area of the ground, finding the tryline is where they excel.

This week they face the NRL's best defence in the Roosters. Accumulating something close to their 24 points per game average has never been more important.

They'll no doubt go about it in their usual way. By dominating the middle and running for the most metres in the competition (1,607m), Souths get up the field well. Damien Cook is then able to pick apart the defensive line out of dummy half to further shrink the defence. From there, they shift the ball while engaging the defence (16.9 line engaged runs per game) to score on the outside.

However, the Roosters will be able to prepare for the onslaught.

No team shifts the ball to the left more than the Rabbitohs' 14.1 times per game. It's quite clearly their preferred avenue in attack, and one the Roosters will have spent the week targeting in practice.

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